enhance: チャンネルに新規の投稿がある場合にバッジを表示させる (#12690)

* 多分できたかも

* 不要なpropsを削除

* 不要なimportを削除

* 縁を付けた

* 枠線の位置を端に寄せた

* やっぱり内側へ寄せることにした

* できたかも

* 修正

* 修正

* クラスにまとめた

* 微調整

* 直せたかも

* importを付け足し

* 多分できたかも

* Update channel.vue

* Update MkMenu.vue

* Update channel.vue

* Update CHANGELOG.md

---------

Co-authored-by: syuilo <Syuilotan@yahoo.co.jp>

packages/frontend/src/pages/channel.vue

@@ -12,7 +12,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 				<XChannelFollowButton :channel="channel" :full="true" :class="$style.subscribe"/>
 				<MkButton v-if="favorited" v-tooltip="i18n.ts.unfavorite" asLike class="button" rounded primary :class="$style.favorite" @click="unfavorite()"><i class="ti ti-star"></i></MkButton>
 				<MkButton v-else v-tooltip="i18n.ts.favorite" asLike class="button" rounded :class="$style.favorite" @click="favorite()"><i class="ti ti-star"></i></MkButton>
-				<div :style="{ backgroundImage: channel.bannerUrl ? `url(${channel.bannerUrl})` : null }" :class="$style.banner">
+				<div :style="{ backgroundImage: channel.bannerUrl ? `url(${channel.bannerUrl})` : undefined }" :class="$style.banner">
 					<div :class="$style.bannerStatus">
 						<div><i class="ti ti-users ti-fw"></i><I18n :src="i18n.ts._channel.usersCount" tag="span" style="margin-left: 4px;"><template #n><b>{{ channel.usersCount }}</b></template></I18n></div>
 						<div><i class="ti ti-pencil ti-fw"></i><I18n :src="i18n.ts._channel.notesCount" tag="span" style="margin-left: 4px;"><template #n><b>{{ channel.notesCount }}</b></template></I18n></div>
@@ -27,7 +27,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 
 			<MkFoldableSection>
 				<template #header><i class="ti ti-pin ti-fw" style="margin-right: 0.5em;"></i>{{ i18n.ts.pinnedNotes }}</template>
-				<div v-if="channel.pinnedNotes.length > 0" class="_gaps">
+				<div v-if="channel.pinnedNotes && channel.pinnedNotes.length > 0" class="_gaps">
 					<MkNote v-for="note in channel.pinnedNotes" :key="note.id" class="_panel" :note="note"/>
 				</div>
 			</MkFoldableSection>
@@ -38,7 +38,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 			<!-- スマホ・タブレットの場合、キーボードが表示されると投稿が見づらくなるので、デスクトップ場合のみ自動でフォーカスを当てる -->
 			<MkPostForm v-if="$i && defaultStore.reactiveState.showFixedPostFormInChannel.value" :channel="channel" class="post-form _panel" fixed :autofocus="deviceKind === 'desktop'"/>
 
-			<MkTimeline :key="channelId" src="channel" :channel="channelId" @before="before" @after="after"/>
+			<MkTimeline :key="channelId" src="channel" :channel="channelId" @before="before" @after="after" @note="miLocalStorage.setItemAsJson(`channelLastReadedAt:${channel.id}`, Date.now())"/>
 		</div>
 		<div v-else-if="tab === 'featured'">
 			<MkNotes :pagination="featuredPagination"/>
@@ -69,6 +69,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 
 <script lang="ts" setup>
 import { computed, watch, ref } from 'vue';
+import * as Misskey from 'misskey-js';
 import MkPostForm from '@/components/MkPostForm.vue';
 import MkTimeline from '@/components/MkTimeline.vue';
 import XChannelFollowButton from '@/components/MkChannelFollowButton.vue';
@@ -89,6 +90,7 @@ import MkFoldableSection from '@/components/MkFoldableSection.vue';
 import { PageHeaderItem } from '@/types/page-header.js';
 import { isSupportShare } from '@/scripts/navigator.js';
 import copyToClipboard from '@/scripts/copy-to-clipboard.js';
+import { miLocalStorage } from '@/local-storage.js';
 
 const router = useRouter();
 
@@ -97,7 +99,7 @@ const props = defineProps<{
 }>();
 
 const tab = ref('overview');
-const channel = ref(null);
+const channel = ref<Misskey.entities.Channel | null>(null);
 const favorited = ref(false);
 const searchQuery = ref('');
 const searchPagination = ref();
@@ -114,14 +116,23 @@ watch(() => props.channelId, async () => {
 	channel.value = await os.api('channels/show', {
 		channelId: props.channelId,
 	});
-	favorited.value = channel.value.isFavorited;
+	favorited.value = channel.value.isFavorited ?? false;
 	if (favorited.value || channel.value.isFollowing) {
 		tab.value = 'timeline';
 	}
+
+	if ((favorited.value || channel.value.isFollowing) && channel.value.lastNotedAt) {
+		const lastReadedAt: number = miLocalStorage.getItemAsJson(`channelLastReadedAt:${channel.value.id}`) ?? 0;
+		const lastNotedAt = Date.parse(channel.value.lastNotedAt);
+
+		if (lastNotedAt > lastReadedAt) {
+			miLocalStorage.setItemAsJson(`channelLastReadedAt:${channel.value.id}`, lastNotedAt);
+		}
+	}
 }, { immediate: true });
 
 function edit() {
-	router.push(`/channels/${channel.value.id}/edit`);
+	router.push(`/channels/${channel.value?.id}/edit`);
 }
 
 function openPostForm() {
@@ -131,6 +142,8 @@ function openPostForm() {
 }
 
 function favorite() {
+	if (!channel.value) return;
+
 	os.apiWithDialog('channels/favorite', {
 		channelId: channel.value.id,
 	}).then(() => {
@@ -139,6 +152,8 @@ function favorite() {
 }
 
 async function unfavorite() {
+	if (!channel.value) return;
+
 	const confirm = await os.confirm({
 		type: 'warning',
 		text: i18n.ts.unfavoriteConfirm,
@@ -152,6 +167,8 @@ async function unfavorite() {
 }
 
 async function search() {
+	if (!channel.value) return;
+
 	const query = searchQuery.value.toString().trim();
 
 	if (query == null) return;
@@ -176,6 +193,10 @@ const headerActions = computed(() => {
 			icon: 'ti ti-link',
 			text: i18n.ts.copyUrl,
 			handler: async (): Promise<void> => {
+				if (!channel.value) {
+					console.warn('failed to copy channel URL. channel.value is null.');
+					return;
+				}
 				copyToClipboard(`${url}/channels/${channel.value.id}`);
 				os.success();
 			},
@@ -186,9 +207,14 @@ const headerActions = computed(() => {
 				icon: 'ti ti-share',
 				text: i18n.ts.share,
 				handler: async (): Promise<void> => {
+					if (!channel.value) {
+						console.warn('failed to share channel. channel.value is null.');
+						return;
+					}
+
 					navigator.share({
 						title: channel.value.name,
-						text: channel.value.description,
+						text: channel.value.description ?? undefined,
 						url: `${url}/channels/${channel.value.id}`,
 					});
 				},